It appears that there were four versions of the Arp Prosoloist.
Yes I think so.
Pro/DGX all seem to have 4075 filter. Never seen a Pro-soloist with one, as they all have 4034.I'm wondering if anyone can confirm this info. Specifically, when did
Arp change from the 4034 filter to the 4075 filter?
Seems to fit, as they are not directly interchangeable (a few component changes are needed).
Were all 4034's potted?
Yes, I think so.
Terje Winther